build: move rustflags/crate-type logic from userspace

We'll need this for both kernel and userspace build.

Bug: 304850822
Change-Id: I655dbcfa00016cf7b39458c5634858f9da9d9158

1 files changed, 168 insertions, 0 deletions

diff --git a/make/rust.mk b/make/rust.mk
new file mode 100644
index 00000000..57173669
--- /dev/null
+++ b/make/rust.mk
@@ -0,0 +1,168 @@
+#
+# Copyright (c) 2023, Google, Inc. All rights reserved
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files
+# (the "Software"), to deal in the Software without restriction,
+# including without limitation the rights to use, copy, modify, merge,
+# publish, distribute, sublicense, and/or sell copies of the Software,
+# and to permit persons to whom the Software is furnished to do so,
+# subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+# Normalize inputs for building Rust modules
+#
+# args:
+# MODULE : name of the module
+# MODULE_SRCS : source files of the module, which should be a single .rs file
+# MODULE_RUST_CRATE_TYPES : list of crate types to build, rlib if not set
+# MODULE_CRATE_NAME : name of the crate, which can differ from module name. this
+# variable's value read outside Make for recursive dependencies, so it must be
+# unconditionally assigned a literal string, e.g. MODULE_CRATE_NAME := foo
+# MODULE_RUST_STEM : The stem of the output .rlib file for this library.
+# 	Defaults to $(MODULE_CRATE_NAME) if left empty.
+# MODULE_RUSTFLAGS : any extra flags to pass to rustc for the module
+# MODULE_RUST_HOST_LIB : whether the module is a host library
+# MODULE_SKIP_DOCS : whether to skip building SDK docs for a module
+#
+# sets:
+# MODULE_RUSTFLAGS
+# MODULE_RUSTDOCFLAGS
+# MODULE_RSOBJS
+# MODULE_RUST_CRATE_TYPES
+# MODULE_RUSTDOC_OBJECT
+# MODULE_EXPORT_RLIBS
+# (for trusted apps):
+# TRUSTY_APP_RUST_MAIN_SRC
+# TRUSTY_APP_RUST_SRCDEPS
+#
+# This file is not intended to be included directly by modules, just used from
+# the library (new) and module (old/kernel) build systems.
+
+ifneq ($(strip $(MODULE_SRCS_FIRST)),)
+$(error $(MODULE) sets MODULE_SRCS_FIRST but is a Rust module, which does not support MODULE_SRCS_FIRST)
+endif
+
+ifneq ($(filter-out %.rs,$(MODULE_SRCS)),)
+$(error $(MODULE) includes both Rust source files and other source files. Rust modules must only contain Rust sources.)
+endif
+
+ifneq ($(words $(filter %.rs,$(MODULE_SRCS))),1)
+$(error $(MODULE) includes more than one Rust file in MODULE_SRCS)
+endif
+
+ifneq ($(filter-out rlib staticlib bin proc-macro,$(MODULE_RUST_CRATE_TYPES)),)
+$(error $(MODULE) contains unrecognized crate type $(filter-out rlib staticlib bin proc-macro,$(MODULE_RUST_CRATE_TYPES)) in MODULE_RUST_CRATE_TYPES)
+endif
+
+ifeq ($(MODULE_CRATE_NAME),)
+$(error $(MODULE) is a Rust module but does not set MODULE_CRATE_NAME)
+endif
+
+# Stem defaults to the crate name
+ifeq ($(MODULE_RUST_STEM),)
+MODULE_RUST_STEM := $(MODULE_CRATE_NAME)
+endif
+
+MODULE_RUSTFLAGS += --crate-name=$(MODULE_CRATE_NAME)
+
+# Throw the module name into the stable crate id so rustc distinguishes
+# between different crates with the same name
+MODULE_RUSTFLAGS += -C metadata=$(MODULE_RUST_STEM)
+
+# Default Rust edition unless otherwise specified
+ifeq ($(MODULE_RUST_EDITION),)
+MODULE_RUST_EDITION := 2021
+endif
+
+MODULE_RUSTFLAGS += --edition $(MODULE_RUST_EDITION)
+
+# Specify paths of dependency libraries because we are not going through Cargo
+MODULE_RUSTFLAGS += $(addprefix --extern ,$(MODULE_RLIBS))
+
+MODULE_RUSTFLAGS_PRELINK := $(MODULE_RUSTFLAGS)
+MODULE_RUSTFLAGS += --emit link
+
+# Allow all lints if the module is in external/. This matches the behavior of
+# soong.
+ifneq ($(filter external/%,$(MODULE_SRCS)),)
+MODULE_RUSTFLAGS += --cap-lints allow
+MODULE_RUSTDOCFLAGS += --cap-lints allow
+endif
+
+MODULE_RSOBJS :=
+
+# default to rlib-only if no crate types specified
+ifeq ($(strip $(MODULE_RUST_CRATE_TYPES)),)
+MODULE_RUST_CRATE_TYPES := rlib
+$(warn MODULE_RUST_CRATE_TYPES defaulting to rlib)
+endif
+
+ifneq ($(filter proc-macro,$(MODULE_RUST_CRATE_TYPES)),)
+MODULE_CRATE_OUTPUT := $(call TOBUILDDIR,lib$(MODULE_RUST_STEM).so)
+MODULE_RSOBJS += $(MODULE_CRATE_OUTPUT)
+$(MODULE_CRATE_OUTPUT): MODULE_RUSTFLAGS := $(MODULE_RUSTFLAGS) \
+	--crate-type=proc-macro --extern proc_macro -C prefer-dynamic
+MODULE_EXPORT_RLIBS += $(MODULE_CRATE_NAME)=$(MODULE_CRATE_OUTPUT)
+
+MODULE_RUSTDOCFLAGS += --crate-type=proc-macro --extern proc_macro
+endif # proc-macro crate
+
+ifneq ($(filter rlib,$(MODULE_RUST_CRATE_TYPES)),)
+MODULE_CRATE_OUTPUT := $(call TOBUILDDIR,lib$(MODULE_RUST_STEM).rlib)
+MODULE_RSOBJS += $(MODULE_CRATE_OUTPUT)
+$(MODULE_CRATE_OUTPUT): MODULE_RUSTFLAGS := $(MODULE_RUSTFLAGS) --crate-type=rlib
+MODULE_EXPORT_RLIBS += $(MODULE_CRATE_NAME)=$(MODULE_CRATE_OUTPUT)
+endif # rlib crate
+
+ifneq ($(filter staticlib,$(MODULE_RUST_CRATE_TYPES)),)
+MODULE_CRATE_OUTPUT := $(call TOBUILDDIR,lib$(MODULE_RUST_STEM).a)
+MODULE_RSOBJS += $(MODULE_CRATE_OUTPUT)
+$(MODULE_CRATE_OUTPUT): MODULE_RUSTFLAGS := $(MODULE_RUSTFLAGS) --crate-type=staticlib
+endif # staticlib crate
+
+ifneq ($(filter bin,$(MODULE_RUST_CRATE_TYPES)),)
+# Used in trusted_app.mk
+TRUSTY_APP_RUST_MAIN_SRC := $(filter %.rs,$(MODULE_SRCS))
+
+TRUSTY_APP_RUST_SRCDEPS := $(MODULE_SRCDEPS)
+endif
+
+ifeq ($(call TOBOOL,$(MODULE_SKIP_DOCS)),false)
+ifneq ($(TRUSTY_SDK_LIB_DIR),)
+MODULE_RUSTDOC_OBJECT := $(TRUSTY_SDK_LIB_DIR)/doc/built/$(MODULE_RUST_STEM)
+endif
+else
+MODULE_RUSTDOC_OBJECT :=
+endif
+
+MODULE_CRATE_OUTPUT :=
+
+ifeq ($(call TOBOOL,$(MODULE_RUST_HOST_LIB)),true)
+# Remove the target-specific flags
+$(MODULE_RSOBJS) $(MODULE_RUSTDOC_OBJECT): ARCH_RUSTFLAGS :=
+$(MODULE_RSOBJS) $(MODULE_RUSTDOC_OBJECT): GLOBAL_RUSTFLAGS := $(GLOBAL_HOST_RUSTFLAGS)
+else
+$(MODULE_RSOBJS) $(MODULE_RUSTDOC_OBJECT): ARCH_RUSTFLAGS := $(ARCH_$(ARCH)_RUSTFLAGS)
+$(MODULE_RSOBJS) $(MODULE_RUSTDOC_OBJECT): GLOBAL_RUSTFLAGS := $(GLOBAL_SHARED_RUSTFLAGS) $(GLOBAL_USER_RUSTFLAGS)
+$(MODULE_RSOBJS) $(MODULE_RUSTDOC_OBJECT): MODULE_RUST_ENV := $(MODULE_RUST_ENV)
+endif
+
+$(MODULE_RSOBJS): MODULE_CRATE_NAME := $(MODULE_CRATE_NAME)
+$(MODULE_RSOBJS): MODULE_RUST_STEM := $(MODULE_RUST_STEM)
+
+$(MODULE_RUSTDOC_OBJECT): RUSTDOC := $(RUST_BINDIR)/rustdoc
+$(MODULE_RUSTDOC_OBJECT): MODULE_RUSTDOC_OUT_DIR := $(TRUSTY_SDK_LIB_DIR)/doc
+$(MODULE_RUSTDOC_OBJECT): MODULE_RUSTDOCFLAGS := $(MODULE_RUSTFLAGS_PRELINK) $(MODULE_RUSTDOCFLAGS)
+$(MODULE_RUSTDOC_OBJECT): MODULE_CRATE_NAME := $(MODULE_CRATE_NAME)